Classifications

• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04W—WIRELESS COMMUNICATION NETWORKS
  • H04W4/00—Services specially adapted for wireless communication networks; Facilities therefor
  • H04W4/30—Services specially adapted for particular environments, situations or purposes
  • H04W4/40—Services specially adapted for particular environments, situations or purposes for vehicles, e.g. vehicle-to-pedestrians [V2P]
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L67/00—Network arrangements or protocols for supporting network services or applications
  • H04L67/01—Protocols
  • H04L67/12—Protocols specially adapted for proprietary or special-purpose networking environments, e.g. medical networks, sensor networks, networks in vehicles or remote metering networks
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04W—WIRELESS COMMUNICATION NETWORKS
  • H04W4/00—Services specially adapted for wireless communication networks; Facilities therefor
  • H04W4/80—Services using short range communication, e.g. near-field communication [NFC], radio-frequency identification [RFID] or low energy communication

Definitions

• the present invention generally relates to the field of wireless exchanges between an on-board system, fitted for example to a vehicle, and an electronic device, forming for example an identifier associated with this vehicle.
• It relates more particularly to a method for transmitting announcement frames, a method for establishing a wireless connection, as well as an associated electronic device and system.
• the method comprises a step of determining the second duration by adding or subtracting, depending on the random value, the duration of the listening phase (denoted t ON in the following) to the product of the first duration T 0 by a number integer (which may be a predetermined integer, for example greater than or equal to 10, or an integer possibly depending on another random value);
• the listening phase has a duration of between 5% and 30% of said first duration (that is to say that the duration t ON is between 0.05.T 0 and 0 ,3.T 0 ).
• the invention proposes an electronic device comprising a control unit and a first communication circuit designed to transmit announcement frames intended for a second communication circuit fitted to a vehicle, the second communication circuit operating according to successive periods having a first predetermined duration and each comprising a listening phase, during which the second communication circuit is capable of detecting an electromagnetic signal, and a rest phase, during which the second communication circuit is inactive, in which the control unit is designed to determine a random value and to determine, based on the random value, a second duration strictly between two consecutive multiples of the first duration, and in which the first communication circuit is designed to emit a announcement frame at a first instant and another announcement frame at a second instant separated from the first instant by the second duration.
• Such a system comprises a vehicle 10, here a motor vehicle, and an electronic device 20 used as an identifier, for example a key or badge for access to the vehicle 10 (or, alternatively, a user terminal, such as a mobile telephone multifunction – or “ smartphone ” according to the commonly used English application, equipped with access rights to the vehicle 10).
• a vehicle 10 here a motor vehicle
• an electronic device 20 used as an identifier, for example a key or badge for access to the vehicle 10 (or, alternatively, a user terminal, such as a mobile telephone multifunction – or “ smartphone ” according to the commonly used English application, equipped with access rights to the vehicle 10).
• the vehicle 10 is equipped with an on-board system 15 including in particular an electronic control unit 11 and a communication circuit 12.
• the electronic control unit 11 comprises for example a microprocessor and at least one memory, for example a rewritable non-volatile memory.
• the memory stores in particular program instructions which allow, when executed by the microprocessor, the implementation by the electronic control unit 11 of the method described below with reference to the .
• the memory can also store values or parameters used during these processes.
• the communication circuit 12 is designed to establish a wireless connection with other electronic devices, here a “ Bluetooth Low Energy ” (or “ BLE ”) type connection.
• the communication circuit 12 is therefore designed in particular to transmit and receive electromagnetic signals (typically of frequency greater than 1 MHz, or even 500 MHz), here in the 2.4 GHz band.
• the communication circuit 12 Due for example to commands received from the electronic control unit 11, the communication circuit 12 carries out successive operating periods having a predetermined duration T 0 and/or each comprising a listening phase, during which the circuit communication circuit 12 is capable of detecting an electromagnetic signal, and a rest phase, during which the communication circuit 12 is inactive.
• the operation of the communication circuit 12 is periodic, each operating period (of predetermined duration T 0 ) comprising a listening phase and a rest phase as defined above.
• the rest phases make it possible to reduce the average electrical consumption of the communication circuit 12 and thus of the on-board system 15.
• the predetermined duration T 0 of the operating periods is for example between 10 ms and 200 ms, and here is worth 100 ms.
• the duration of the listening phase is for example between 5% and 30% of the operating period.
• t ON the duration of a listening phase. (The duration t ON is therefore here between 0.05.T 0 and 0.3.T 0 .)
• the electronic device 20 generally worn by a user of the vehicle 10, is used as an identifier to authorize and/or enable the control of certain functionalities of the vehicle 10 (for example the unlocking of the doors of the vehicle 10), in particular when it is approached of the vehicle 10.
• the electronic device 20 may optionally also include control buttons, using which the user can control at least some of the aforementioned functionalities or other functionalities of the vehicle 10.
• control unit 21 could be produced in the form of a specific application integrated circuit.
• the electromagnetic signals exchanged between the communication circuits 12, 22 can also be used to evaluate the distance separating the electronic device and the vehicle 10 (precisely the distance separating the communication circuits 12, 22), as also explained below.
• step E6 the control unit 21 determines a random value a, for example in the case described here by calling a dedicated function (random drawing function) within the microprocessor forming the control unit 21.
• a dedicated function random drawing function
• the duration ⁇ t is determined as follows:
• two successive announcement frames are transmitted at respective times separated by a duration ⁇ t which verifies the conditions stated above with regard to the ADV2 announcement frame, namely that this duration ⁇ t depends on a random value (which may be different for each frame transmitted) and is strictly between two consecutive multiples of the predetermined duration T 0 (the pair of consecutive multiples concerned may be distinct from one frame to another ).
• nT 0 ⁇ ⁇ t ⁇ (n+1).T 0 with n an integer greater than or equal to 2, and preferably greater than or equal to 5 (n may vary from one announcement frame to another as already indicated ).
• the instant of transmission of the announcement frames depends on a random value (determined in step E6) so that two electronic devices of the type of electronic device 20 and same design (which is the case for example when two vehicle users respectively carry two similar identifiers) will (with some exceptions) emit an announcement frame at distinct times, which makes it possible to avoid interference between these two electronic devices in their exchanges with the communication circuit 12 which equips the vehicle.
• the electronic control unit 11 can then command, in step E14, the communication circuit 12 to respond to the announcement frame ADVi transmitted by the electronic device 20, typically by sending a connection request CONN_REQ to the communication circuit. 22 of identifier 20 (step E16).
• the communication circuit 22 of the electronic device 20 receives the connection request CONN_REQ in step E18.
• a wireless connection can thus be set up between the on-board system 15 and the identifier 20 in step E20 by means of establishing a connection between the communication circuit 12 of the on-board system 15 and the communication circuit 22 of the identifier 20 in accordance with the communication protocol concerned (here the BLE protocol already mentioned).
• the data exchanged between the electronic device 20 and the on-board system 15 are encrypted (typically by means of a cryptographic encryption algorithm, using for example the cryptographic key K shared by the electronic control unit 11 and the control unit 21 as already indicated) during their exchange between the communication circuit 12 of the on-board system 15 and the communication circuit 22 of the electronic device 20.
• the encryption used is for example that provided for in the context of the protocol concerned data exchange D, here the BLE protocol.
• the control unit 21 receives the CH value via the communication circuit 22 (step E24).
• the control unit 21 then commands (step E28) the communication circuit 22 to transmit the response RS via the established wireless link (between the communication circuit 12 and the communication circuit 22), and thus to the electronic control unit 11.
• the electronic control unit 11 therefore receives the RS response in step E30, via the communication circuit 12.
• the electronic control unit 11 can thus verify the response RS received in step E32, here by applying to the response RS a cryptographic processing algorithm, for example a decryption algorithm, using the cryptographic key K, and by checking whether the result obtained is indeed identical to the CH value sent in step E22.
• a cryptographic processing algorithm for example a decryption algorithm
• step E32 If (and only if) the verification is correctly carried out in step E32 (which demonstrates that the electronic device actually memorizes the cryptographic key K), the electronic device 20 is authenticated by the electronic control unit 11; the electronic control unit 11 can then authorize certain actions such as unlocking the vehicle 10.

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• Engineering & Computer Science (AREA)
• Computer Networks & Wireless Communication (AREA)
• Signal Processing (AREA)
• Health & Medical Sciences (AREA)
• Computing Systems (AREA)
• General Health & Medical Sciences (AREA)
• Medical Informatics (AREA)
• Mobile Radio Communication Systems (AREA)
• Communication Control (AREA)
• Synchronisation In Digital Transmission Systems (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=84370231

Family Applications (1)

Country Status (4)

Family Cites Families (2)

• 2022
  • 2022-10-17 FR FR2210655A patent/FR3141026A1/fr active Pending
• 2023
  • 2023-09-19 CN CN202380073419.7A patent/CN120077686A/zh active Pending
  • 2023-09-19 WO PCT/EP2023/075783 patent/WO2024083426A1/fr not_active Ceased
  • 2023-09-19 EP EP23768921.1A patent/EP4606133A1/de active Pending

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